In the automobile domain, key housings including an electronic part used to identify a user of the vehicle by exchanging electromagnetic signals and a mechanical part containing an emergency key are known, for example from document EP 0 987 389.
Such housings are particularly practical since they enable the key to be concealed within the very structure of the housing protecting the key. This is particularly advantageous since the user only requires this emergency key in the event of electrical failure, for example a battery failure in the electronic part or a battery failure of the vehicle.
This arrangement also prevents the key insert from snagging in the user's pockets and damaging the user's clothes. This arrangement also makes it possible to significantly reduce the size of the housing.
In document EP 0 987 389, as cited above, the emergency key includes a head forming a gripping portion and a metal insert that can be used as a mechanical emergency key, the head being rigidly attached perpendicular to the metal insert.
To house this emergency key, the housing includes, along one of the edges of same, a seat forming a sheet designed to receive the insert and the key head is clicked onto a corresponding opening of the housing.
Nonetheless, inside the housing, the key may still have some degree of freedom of movement, which may result in unwanted noises and impacts in the event of vibration.